Abstract

The Toll-like receptors (TLRs), 2, 4 and 9 are important to immunity against Trypanosoma cruzi, etiologic agent of Chagas disease. Intracellular receptors, including NLRP3 and AIM2, associate to ASC forming a complex that active caspase-1, called inflammasome. This complex is required for cleavage of the active forms of the IL-1β and IL-18. Recently, we show that ASC inflammasome is necessary to control T. cruzi infection, however the receptors that participate in this signalizing are not complete clear. Here, we investigated the participation of NLRP3 and AIM2 in the immune response against T. cruzi. First, we found high IL-1β production and caspase-1 activation in BMMs from WT mice, but not from NLRP3-/- and AIM2-/- mice. To understand the role of the inflammasome pathway during T. cruzi infection, WT, caspase-1-/-, ASC-/-, AIM2-/- and NLRP3-/- mice were infected with Y strain of T.cruzi. Our results showed that ASC-/- and caspase-1-/- mice presented higher mortality, whereas WT, AIM3-/- and NLRP3-/- are resistant to infection, suggesting more than one NLR is necessary to confer resistance for T. cruzi infection. In addition, caspase-1-/-, ASC-/-, AIM2-/- and NLRP3 BMMs presented higher parasitism and reduced amount of Nitric oxide (NO) production. Together, these results suggest that AIM2 and NLRP3 via ASC inflammasome participate of the infection against T. cruzi. Financial Support: FAPESP